Ferromagnetic polar metals via epitaxial strain: a case study of SrCoO${}_3$

Abstract

While polar metals are a metallic analogue of ferroelectrics, magnetic polar metals can be considered as a metallic analogue of multiferroics. There have been a number of attempts to integrate magnetism into a polar metal by synthesizing new materials or heterostructures. Here we use a simple yet widely used approach--epitaxial strain in the search for intrinsic magnetic polar metals. Via first-principles calculations, we study strain engineering of a ferromagnetic metallic oxide SrCoO${}_3$, whose bulk form crystallizes in a cubic structure. We find that under an experimentally feasible biaxial strain on the $ab$ plane, collective Co polar displacements are stabilized in SrCoO${}_3$. Specifically, a compressive strain stabilizes Co polar displacements along the $c$ axis, while a tensile strain stabilizes Co polar displacements along the diagonal line in the $ab$ plane. In both cases, we find an intrinsic ferromagnetic polar metallic state in SrCoO${}_3$. In addition, we also find that a sufficiently large biaxial strain ($>4\%$) can yield a ferromagnetic-to-antiferromagnetic transition in SrCoO${}_3$. Our work demonstrates that in addition to yielding emergent multiferroics, epitaxial strain is also a viable approach to inducing magnetic polar metallic states in quantum materials.

arXiv comment19 pages, 6 figures

References in corpus (12)

• A ferroelectric-like structural transition in a metal
• Magnetic and electric phase control in epitaxial EuTiO${}_3$ from first principles
• Epitaxial-strain-induced multiferroicity in SrMnO${}_3$ from first principles
• Comparison of the Electronic Structures and Energetics of Ferroelectric LiNbO3 and LiTaO3
• Lattice normal modes and electronic properties of the correlated metal LaNiO${}_3$
• Coupled magnetic-ferroelectric metal-insulator transitions in epitaxially-strained SrCoO${}_3$ from first principles
• Design of a multifunctional polar metal via first-principles high-throughput structure screening
• Manipulating Berry curvature of SrRuO3 thin films via epitaxial strain
• Strain-induced magnetic phase transition in SrCoO${}_{3-\delta }$ thin films
• Pressure-induced enhancement of non-polar to polar transition temperature in metallic LiOsO${}_3$
• Coexistence of polar displacements and conduction in doped ferroelectrics: an ab initio comparative study
• Coupled magnetic and structural phase transitions in the antiferromagnetic polar metal Pb2CoOsO6 under pressure